The Profit Toolkit
Every calculator on this site, plus a profit log and monthly P&L, in one spreadsheet you own. Works in Excel, Google Sheets and Numbers. No logins, no subscriptions, nothing connected to your seller accounts.
Rates verified on
$29
One-time. Free updates for 12 months when fees or postage change.
Checkout by Stripe. Instant download. If it doesn't help, reply within 30 days for a refund.
What's inside
Start here
How to use each tab in five minutes, and what the colors mean.
Net calculators
eBay, Mercari, Poshmark, Depop, Whatnot, Etsy and Amazon media, each with its verified fee table. Type a price, see your profit.
Where to sell
One item across every platform, side by side.
Minimum-price builder
The floor price for your repricer: fees, postage, packaging and target profit in, minimum total out, for 1-10 lb at once.
Postage tables
Media Mail 1-70 lb and Ground Advantage commercial and retail, Zones 1-9, from USPS Notice 123.
Profit log
One row per item: cost, platform, sale price, fees and profit, filled in by formula.
Monthly P&L
Sales, fees, postage, cost of goods and profit by month, built from your log.
Sources
Every rate with its official link and the date we checked it.
Who it's for
Sellers who want their numbers in one place: what each platform takes, what postage costs, the lowest price that's still worth selling at, and what they actually made this month. The fee tables come from the same verified data as this site (last checked 2026-10-14).
The free calculators on this site will stay free. The Toolkit is for working offline, logging your own sales and keeping a monthly profit and loss.
Get it the day it's available
Subscribe and we'll send the link (and the free weekly Index).